doc/guide/localhost/IntroduceLoops

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  26 <h1>IntroduceLoops</h1>
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  28 <div id="content">
  29 <div id="preamble">
  30 <div class="sectionbody">
  31 <div class="paragraph"><p><a href="IntroduceLoops">IntroduceLoops</a> is an optimization pass for the <a href="SSA">SSA</a>
  32 <a href="IntermediateLanguage">IntermediateLanguage</a>, invoked from <a href="SSASimplify">SSASimplify</a>.</p></div>
  33 </div>
  34 </div>
  35 <div class="sect1">
  36 <h2 id="_description">Description</h2>
  37 <div class="sectionbody">
  38 <div class="paragraph"><p>This pass rewrites any <a href="SSA">SSA</a> function that calls itself in tail
  39 position into one with a local loop and no self tail calls.</p></div>
  40 <div class="paragraph"><p>A <a href="SSA">SSA</a> function like</p></div>
  41 <div class="listingblock">
  42 <div class="content monospaced">
  43 <pre>fun F (arg_0, arg_1) = L_0 ()
  44   ...
  45   L_16 (x_0)
  46     ...
  47     F (z_0, z_1) Tail
  48   ...</pre>
  49 </div></div>
  50 <div class="paragraph"><p>becomes</p></div>
  51 <div class="listingblock">
  52 <div class="content monospaced">
  53 <pre>fun F (arg_0', arg_1') = loopS_0 ()
  54   loopS_0 ()
  55     loop_0 (arg_0', arg_1')
  56   loop_0 (arg_0, arg_1)
  57     L_0 ()
  58   ...
  59   L_16 (x_0)
  60     ...
  61     loop_0 (z_0, z_1)
  62   ...</pre>
  63 </div></div>
  64 </div>
  65 </div>
  66 <div class="sect1">
  67 <h2 id="_implementation">Implementation</h2>
  68 <div class="sectionbody">
  69 <div class="ulist"><ul>
  70 <li>
  71 <p>
  72 <a href="https://github.com/MLton/mlton/blob/master/mlton/ssa/introduce-loops.fun"><span class="monospaced">introduce-loops.fun</span></a>
  73 </p>
  74 </li>
  75 </ul></div>
  76 </div>
  77 </div>
  78 <div class="sect1">
  79 <h2 id="_details_and_notes">Details and Notes</h2>
  80 <div class="sectionbody">
  81 <div class="paragraph"><p></p></div>
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